SERVICE MANUAL FOR M28 ONE-CHIP CHASSIS

Size: px
Start display at page:

Download "SERVICE MANUAL FOR M28 ONE-CHIP CHASSIS"

Transcription

1 TCL OVERSEAS HOLDINGS LIMITED Service Manual 3 SERVICE MANUAL FOR M28 ONE-CHIP CHASSIS PART I. Servicing Precautions When working, the unit is with high voltage about 25KV inside. So, to avoid the risk of electric shock, be careful to adjust the chassis! 1. Only qualified personnel should perform service procedures. 2. All specification must be met over line voltage ranger of 110V AC to 240V AC 50Hz/60Hz. 3. Do not operate in WET/DAMP conditions. 4. Portions of the power supply board are hot ground. The remaining boards are cold ground. 5. Discharge of CRT anode should be done only to CRT ground strap. 6. When fuse blow, ensure to replace a fuse with the same type and specification. 7. Keep the wires away from the components with high temperature or high voltage. 8. When replacing the resister with high power, keep it over the PCB about 10mm. 9. The CRT anode high voltage has been adjusted and set in the factory. When repairing the chassis, do not make the high voltage exceed 27.5KV (The beam current is 0uA). Generally, the high voltage is set on 25.5KV±1.5KV (The beam current is 700uA). * The values of parameters above are for information only. 10. Before return the fixed unit, do check all the covering of wires to ensure that not fold or not short with any metal components. Check the entire protection units, such as control knobs, rear cabinet & front panel, insulation resister & capacitor, mechanical insulators and so on. 11. There are some mechanical and electrical parts associating with safety (EMC) features (Generally related to high voltage or high temperature or electric shock), these features cannot be found out from the outside. When replace these components, perhaps the voltage and power suit the requirements, but efficient X-ray protection may not be provided. All these components are marked with in the schematic diagram. When replace these, you d better look up the components listed in this manual. If the component you replaced not has the same safety (EMC) performance, harmful X-ray may be produced.

2 4 Service Manual TCL OVERSEAS HOLDINGS LIMITED PART II -Product Specification 1. Ambient Conditions: 1.1 Ambient Temperatures: a. Operating: -10 ~ +40 b. Storage: -15 ~ Humidity a. Operation: <80% b. Storage: <90% 1.3 Air Pressure: 86kpa ~ 106kpa 2. GENERAL SPECIFICATION 2.1 MPU & Chroma IC: TMPA8803CSN (One-Chip) 2.2 TV Broadcasting System PAL DK/BG SECAM DK/BG NTSC 3.579/4.43 AV MODE 2.3 Scanning Lines & Frequencies 525/625 lines KHz/15.75KHz 50/60Hz 2.4 Color Sub-Carrier: 4.433MHz/3.579MHz 2.5 IF: Picture 38.9MHz Sound 5.5/6.5MHz 2.6 Power Consumption: 80W 2.7 Power Supply: AC 220V 50Hz±10% 2.8 Audio Output Power (7%THD): 4W + 4W 2.9 Aerial Input Impedance: 75 Unbalanced Din Jack Ant.Input 2.10 Product Safety Requirement: VDE Approval 2.11 Product EMC/EMI Requirement: FTZ Approval 3. Basic Features of Controller 3.1 Channel Tuning Method: Voltage Synthesizer

3 TCL OVERSEAS HOLDINGS LIMITED Service Manual Presettable Program: 100 Programs 3.3 Tuning for VHF and UHF Bands: Auto/Manual/Fine Tuning 3.4 Picture and Sound Adjustment Bright, Contrast, Color and Volume Control TINT Control (NTSC) Sharpness Control 3.5 OSD General Features (Volume, Brightness, Contrast, Color, Program, Band, Auto Search, Manual, Tune, Muting, AV and Sleep Timer) NICAM and Dual Language German Stereo Indicator 3.6 Sleep Timer: Minutes with 10Min.Increment 3.7 Auto Off When No Broadcasting Signal: 15 min 3.8 Full Function Infrared Remote Control 3.9 Remote Effective Distance: 8m 4. Construction of Front Panel Main Power Switch Remote Sensor Standby Indicator Menu Select TV/AV Select Program and Volume Up/Down 5. Construction of Real Panel 75 Aerial Terminal RCA Socket Audio-R+L In/Out, Video- In/Out Y/U/V Input 6. Other Information 6.1 Colour Temperature: 9300K X=284 Y= Magnetic Field: Bv=0.2~0.5Gs

4 6 Service Manual TCL OVERSEAS HOLDINGS LIMITED PART III. Brief Introduction on Chassis AV INPUT/ OUTPUT RF IN TUNER SAW NICAM BD AUDIO AMP XTAL OSC TMPA8803CPN(M28) R/G/B CRT DRIVE I 2 C BUS E 2 PROM INFRARED REMOTE CONTROL REMOTE CONTROL RECEIVER V OUTPUT DPC H DRIVE H OUTPUT FBT SWITCH POWER MC44608 The TV signal is amplified by the frequency mixing circuit of the tuner. Then the tuner output PIF and SIF signals. The IF signals are amplified about 20dB by the pre IF amplifier (Q101). Having passed the SAW, the IF signals go into the TMP8803CPN from pin 42, 41. The IF signal pass the video detect circuit to generate CVBS signal. Then the processor deals the signal with luminance and chroma separation. The processor deals the luminance signal with Y-Delay, Y-Gamma correction, Y-hf compensation and black strength, all which ensure that there are enough bandwidth and gain with Y signal, so that the resolution of picture detail is improved and the Y signal is well timed with chroma signal. The processor also deals the chroma signal with chroma sub-carrier recovery, color system recognition and color signal decoding, then outputs B-Y and R-Y color difference signal. A matrix circuit converts the color difference signal (Y, B-Y and R-Y) into primary color signal (R/G/B). On the other hand, the processor separated the horizontal and vertical sync signal from the CVBS signal which was generated by video detect circuit. Having passed the horizontal (or vertical) frequency dividing circuit, the H (or V) OSC signal, which be generated by H-AFC (or V-AFC), is changed to H (or V) drive signal. The H/V drive signal make the horizontal/vertical circuits and scan output circuit to generate H/V saw tooth wave

5 TCL OVERSEAS HOLDINGS LIMITED Service Manual 7 1.Channel Section The RF signal is converted into IF signal by the tuner. Then the IF signal cross the IF amplifier circuit (pre IF amplifier) to get a gain about 15dB. By the coupling capacitance (c110) and the match resistance (R ), the input resistance of the pre-if amplifier match with the tuner. The signals pass a parallel connection circuit with voltage NFB, which combines the advantages of low output impedance, of wide dynamic range and of less components. R116 is a voltage NFB component, which is used to adjust the gain in the pass band. Having been amplified by the IF amplifier, the IF signal pass a SAW, and then come into TMPA8803CSN from pin41 and pin42 with balance. The processor deal the IF signal with IF detection, PLL demodulation, IF AGC, AFC, video peak detection, and color system recognition etc., then output a AGC signal from pin 43 to the tuner to adjust the input amplitude of IF signal. R217, C218 and C219 make up of picture IF PLL circuit, which is used to control IF detection. IC201 output a sound IF signal from pin 31 and a video signal, which will be amplified by Q209, from pin30. The processor output a sound system control signal to Q208. If the processor output a high level from pin59 (sound detection), Q208 is on, and a video signal is separated from the IF signal by a trap. With capacitance coupling, the video signal comes into IC201 from pin26, and then it is selected by inner switches and output from pin45. Having come out, the video signal will be amplified by Q210, and a sync signal will be separated by a sync separate circuit which is made up by C208, Q202 and Q203. Then the video come into inner 870X CPU module from IC201 pin62 to detect whether the signal is live signal. Tuning control and band switch control circuits The processor output a tuning control signal from pin60. The control signal will pass Q103 common emitter amplifying circuit, then an integrating circuit. Finally, it is added to the VT terminal to provide all channels tuning voltage for the tuner to stabilize the channels. 2.Vertical Output Section TMPA8803CSN outputs vertical saw-tooth wave from pin 16. It come to pin5 of LA7840 with DC coupling, and is amplified by inner difference amplifier. Pin4 of LA7840 is the same phase input terminal. R307 and R308 are DC offset resistances. C305 is a filter capacitor. In application to M28, pin4 of la7840 is fixed as the DC amplify ref terminal. The amplified saw tooth wave come out la7840 from pin2 and make the deflect coil to generate the deflect current. R314 and C301 filtrate the inductive interference from the horizontal deflect coil. R317 and C309 are used to eliminate spurious oscillation generated by the deflect coil and distributed capacitance resonance. C308, R313, C307 and accessory circuit are in charge of draw AC saw tooth wave out at the deflect coil terminal connected with R315 & R316, and feedback to the input terminal of la7840 (pin5) to correct the linearity of horizontal scan. C306 is a high frequency decoupling capacitor. D301 and C303 make up of a voltage pump up circuit. La7840 output a vertical kickback impulse from pin7 to locate the OSD characters. 3.Horizontal Output Section The processor outputs horizontal drive impulse from pin 13. The drive impulse is done with voltage division by R238 and R401, and then comes to the base of the drive triode (Q401). C401 is used to eliminate the noise in the H drive impulse. T401 is a horizontal drive transformer. Q402 is a horizontal output triode with a damper inside. L402 is connected with the emitter of the horizontal output diode to eliminate the radiation and to improve the distortions at the cross of vertical and horizontal white

6 8 Service Manual TCL OVERSEAS HOLDINGS LIMITED lines. C406 and C402 are retrace capacitors and C421 is an s-correct capacitor. L441 and L442 are horizontal linear inductors. R441 is used to eliminate the parasitic oscillation caused by horizontal linear inductors. C420, R413 and D411 are used to correct the M-distortion in horizontal direction. C422, R415 and R415A are coupling components for the horizontal retrace impulse, which are feed back to pin 12 of TMPA8803CSN. D404 is a negative peak-killer diode. Horizontal scanning distortion and the method to compensate it The deflect coil and the horizontal output triode have some resistance R while they are ducting. The resistance R will cause the non-linear distortion, which means that the right direction scanning speed of the electron beam becomes slower, and the right of the raster is compressed to generate distortion. We use a horizontal linear adjuster to compensate this kind of distortion. We use L412 and L411 as the H linear adjusters in H scanning section of M28 chassis. R411, which is parallel connected with L411 and L412, is a despiking resistance for preventing the oscillation by compensating inductor and the stray capacitance. The linear adjuster is a transductor coil with a magnetic core inside. If the current, which pass the linear adjuster coil, increase to a certain value, the magnetic core becomes saturated to decrease the inductance of the linear adjustment inductor. If the +B is steady, the increase speed of Iy is faster to compensate the reducing of deflecting current by the resistance R mention above. We can adjust the magnetic core to chang the inductance of the linear compensate inductor to adjust the H linearity. The EHT generation circuit The FBT supply the anode high voltage, focus voltage and screen voltage for M28 chassis. D401 and C408 are in charge of regulating the primary impulse of the transformer to output a voltage of 190V for the video amplifiers. The ( 10 ) ~ ( 8 ) coils of the FBT supply the heater with power. Having passed the divider and clipping circuits, which are maded up by R415, R415A, C422 and D404, the H retrace impulses getting out from ( 3 ) ~ ( 10 ) coils are inputed to pin12 of TMPA8803CSN to generate sand castle impulse. To limit the beam current in a safe range, we add a ABL circuit in M28 chassis. We add two sampling resistances (R414, R415) between +24V power supply and pin7 of the FBT. The voltage at the joint of the two resistances is feed back to pin27 of TMPA8803CSN to control bright and contrast to limit the beam current. It is also in charge of regulating EHT. C410 is a fliter capacitor for ABL voltage. The impulses, which are induced by secondary coil 5, are changed to 12V once passed the regulating and fliting circuit made up by D402 and C413. IC401 change 12V power supply to 9V for many circuits, such as R/G/B output circuit of TMPA8803CSN, IC4053, pre IF-amplifier circuit, bright dots killer circuit and S terminal circuit. IC402 outputs a 5V power supply for the keyboard circuit. C418, C417, C423 and C425 are fliter capacitors. D402 and C413 are incharge of regulating and flitering for the output of coil6 to supply the V scanning output section with 24V power. The 24V is added to the upper terminal of the V deflecting yoke as the DC bias for the movement of V center. Extension distortion and compensation This kind of distortion is mainly caused by the structure of CRT. Due to the srcreen of SF CRT is not a ture flat screen, the distances from the deflecting center to the screen are not the same. The scanning speed of the electron beam is uniform. If the electron beam scannning the screen equally with the

7 TCL OVERSEAS HOLDINGS LIMITED Service Manual 9 effect of ture linear sawtooth current, the E-W sides of the picture are stretched. That is the extension distortion. Usually, we add a S-correct capacitor in series with the deflecting coil to compensate this kind of distortion. The integral character of S-correct capacitor make the current waveform S shape. So the scanning speed of electron beam at the center of screen is faster than the one at the side. So this action can correct the extension distortion. C421 is a S-correct capacitor. The capacitance is inverse ratio with the correcting effect.

8 10 Service Manual TCL OVERSEAS HOLDINGS LIMITED PART IV. IC Pin Description 1. MC44608-High Voltage PWM Controller Pin Name Description 1 Demag The Demag pin offers 3 different functions: Zero voltage crossing detection (50mV), 24 A current detection and 120 A current detection. The 24 A level is used to detect the secondary reconfiguration status and the 120 A level to detect an Over Voltage status called Quick OVP. The Current Sense pin senses the voltage developed on the series resistor inserted in the source of the power MOSFET. When Isense reaches 1V, the Driver output (pin 5) is disabled. This is known as the Over Current Protection 2 3 I sense Control Input function. A 200 A current source is flowing out of the pin 3 during the start up phase and during the switching phase in case of the Pulsed Mode of operation. A resistor can be inserted between the sense resistor and the pin 3, thus a programmable peak current detection can be performed during the SMPS stand by mode. A feedback current from the secondary side of the SMPS via the opto coupler is injected into this pin. A resistor can be connected between this pin and GND to allow the programming of the Burst duty cycle during the Stand by mode. 4 Ground This pin is the ground of the primary side of the SMPS. 5 Driver The current and slew rate capability of this pin are suited to drive Power MOSFETs. This pin is the positive supply of the IC. The driver output gets disabled when 6 V CC the voltage becomes higher than 15V and the operating range is between 6.6V and 13V. An intermediate voltage level of 10V creates a disabling condition called Latched Off phase. 7 This pin is to provide isolation between the Vi pin 8 and the VCC pin 6. 8 V i This pin can be directly connected to a 500V voltage source for start up function of the IC. During the Start up phase a 9 ma current source is internally delivered to the VCC pin 6 allowing a rapid charge of the VCC capacitor. As soon as the IC starts up, this current source is disabled.

9 TCL OVERSEAS HOLDINGS LIMITED Service Manual 11 OPERATING DESCRIPTION Regulation The pin 3 senses the feedback current provided by the opto-coupler. During the switching phase the switch S2 is closed and the shunt regulator is accessible by the pin 3. The shunt regulator voltage is typically 5V. The dynamic resistance of the shunt regulator represented by the zener diode is 20. The gain of the Control input is given on Figure 10 which shows the duty cycle as a function of the current injected into the pin 3. A 4KHz filter network is inserted between the shunt regulator and the PWM comparator to cancel the high frequency residual noise. The switch S3 is closed in Stand by mode during the Latched Off Phase while the switch S2 remains open. (See section PULSED MODE DUTY CYCLE CONTROL). The resistor Rdpulsed (Rduty cycle burst) has no effect on the regulation process. This resistor is used to determine the burst duty cycle described in the chapter Pulsed Duty Cycle Control on page 8. PWM Latch The MC44608 works in voltage mode. The on time is controlled by the PWM comparator that compares the oscillator sawtooth with the regulation block output. The PWM latch is initialized by the oscillator and is reset by the PWM comparator or by the current sense comparator in case of an over current. This configuration ensures that only a single pulse appears at the circuit output during an oscillator cycle. Current Sense The inductor current is converted to a positive voltage by inserting a ground reference sense resistor R Sense in series with the power switch. The maximum current sense threshold is fixed at 1V. The peak current is given by the following

10 12 Service Manual TCL OVERSEAS HOLDINGS LIMITED equation: Ipk max = 1/R sense ( ) (A) In stand by mode, this current can be lowered as due to the activation of a 200 A current source: Ipk MAX-STBY The current sense input consists of a filter (6k, 4pF) and of a leading edge blanking. Thanks to that, this pin is not sensitive to the power switch turn on noise and spikes and practically in most applications, no filtering network is required to sense the current. Finally, this pin is used: as a protection against over currents (I sense > I) as a reduction of the peak current during a Pulsed Mode switching phase. The overcurrent propagation delay is reduced by producing a sharp output turn off (high slew rate). This results in an abrupt output turn off in the event of an over current and in the majority of the pulsed mode switching sequence. Demagnetization Section The MC44608 demagnetization detection consists of a comparator designed to compare the V CC winding voltage to a reference that is typically equal to 50mV. This reference is chosen low to increase effectiveness of the demagnetization detection even during start up. A latch is incorporated to turn the demagnetization block output into a low level as soon as a voltage less than 50 mv is detected, and to keep it in this state until a new pulse is generated on the output. This avoids any ringing on the input signal which may alter the demagnetization detection. For a higher safety, the demagnetization block output is also directly connected to the

11 TCL OVERSEAS HOLDINGS LIMITED Service Manual 13 output, which is disabled during the demagnetization phase. The demagnetization pin is also used for the quick, programmable OVP. In fact, the demagnetization input current is sensed so that the circuit output is latched off when this current is detected as higher than 120 A. This function can be inhibited by grounding it but in this case, the quick and programmable OVP is also disabled. Oscillator The MC44608 contains a fixed frequency oscillator. It is built around a fixed value capacitor CT succesively charged and discharged by two distinct current sources ICH and IDCH. The window comparator senses the CT voltage value and activates the sources when the voltage is reaching the 2.4V/4V levels. The complete demagnetization status DMG is used to inhibit the recharge of the CT capacitor. Thus in case of incomplete transformer demagnetization the next switching cycle is postpone until the DMG signal appears. The oscillator remains at 2.4V corresponding to the sawtooth valley voltage. In this way the SMPS is working in the so called SOPS mode (Self Oscillating Power Supply). In that case the effective switching frequency is variable and no longer depends on the oscillator timing but on the external working conditions (Refer to DMG signal in the Figure 5). The OSC and Clock signals are provided according to the Figure 5. The Clock signals correspond to the CT capacitor discharge. The bottom curve represents the current flowing in the sense resistor Rcs. It starts from zero and stops when the sawtooth value is equal to the control voltage Vcont. In this way the SMPS is regulated with a voltage mode control. Overvoltage Protection The MC44608 offers two OVP functions: a fixed function that detects when V CC is higher than 15.4V a programmable function that uses the demag pin. The current flowing into the demag pin is mirrored and compared to the reference current Iovp (120 A). Thus this OVP is quicker as it is not impacted by the V CC inertia and is called QOVP. In both cases, once an OVP condition is detected, the output is latched off until a new circuit

12 14 Service Manual TCL OVERSEAS HOLDINGS LIMITED START UP. Start up Management The Vi pin 8 is directly connected to the HV DC rail Vin. This high voltage current source is internally connected to the V CC pin and thus is used to charge the V CC capacitor. The VCC capacitor charge period corresponds to the Start up phase. When the V CC voltage reaches 13V, the high voltage 9mA current source is disabled and the device starts working. The device enters into the switching phase. It is to be noticed that the maximum rating of the Vi pin 8 is 700V. ESD protection circuitry is not currently added to this pin due to size limitations and technology constraints. Protection is limited by the drain substrate junction in avalanche breakdown. To help increase the application safety against high voltage spike on that pin it is possible to insert a small wattage 1k series resistor between the Vin rail and pin 8. The Figure 6 shows the V CC voltage evolution in case of no external current source providing current into the V CC pin during the switching phase. This case can be encountered in SMPS when the self supply through an auxiliary winding is not present (strong overload on the SMPS output for example). The Figure 16 also depicts this working configuration. In case of the hiccup mode, the duty cycle of the switching phase is in the range of 10%. Mode Transition was observed The LW latch Figure 7 is the memory of the working status at the end of every switching sequence. Two different cases must be considered for the logic at the termination of the SWITCHING PHASE: 1. No Over Current

13 TCL OVERSEAS HOLDINGS LIMITED Service Manual An Over Current was observed These 2 cases are corresponding to the signal labeled NOC in case of No Over Current and OC in case of Over Current. So the effective working status at the end of the ON time memorized in LW corresponds to Q=1 for no over current and Q=0 for over current. This sequence is repeated during the Switching phase. Several events can occur: 1. SMPS switch OFF 2. SMPS output overload 3. Transition from Normal to Pulsed Mode 4. Transition from Pulsed Mode to Normal Mode 1. SMPS SWITCH OFF When the mains is switched OFF, so long as the bulk electrolithic bulk capacitor provides energy to the SMPS, the controller remains in the switching phase. Then the peak current reaches its maximum peak value, the switching frequency decreases and all the secondary voltages are reduced. The V CC voltage is also reduced. When V CC is equal to 10V, the SMPS stops working. 2. Overload In the hiccup mode the 3 distinct phases are described as follows (refer to Figure 6): The SWITCHING PHASE: The SMPS output is low and the regulation block reacts by increasing the ON time (dmax = 80%). The OC is reached at the end of every switching cycle. The LW latch (Figure 7) is reset before the VPWM signal appears. The SMPS output voltage is low. The V CC voltage cannot be maintained at a normal level as the auxiliary winding provides a voltage which is also reduced in a ratio similar to the one on the output (i.e. Vout nominal / Vout short circuit). Consequently the V CC voltage is reduced at an operating rate given by the combination V CC capacitor value together with the I CC working consumption (3.2mA) according to the equation 2. When V CC crosses 10V the WORKING PHASE gets terminated. The LW latch remains in the reset status. The LATCHED OFF PHASE: The V CC capacitor voltage continues to drop. When it reaches 6.5V this phase is terminated. Its duration is governed by equation 3. The START UP PHASE is reinitiated. The high voltage start up current source ( I CC1 = 9mA) is activated and the MODE latch is reset. The V CC voltage ramps up according to the equation 1. When it reaches 13V, the IC enters into the SWITCHING PHASE. The NEXT SWITCHING PHASE: The high voltage current source is inhibited, the MODE latch (Q=0) activates the NORMAL mode of operation. Figure 2 shows that no current is injected out pin 2. The over current sense level corresponds to 1V. As long as the overload is present, this sequence repeats. The SWITCHING PHASE duty cycle is in the range of 10%.

14 16 Service Manual TCL OVERSEAS HOLDINGS LIMITED 3. Transition from Normal to Pulsed Mode In this sequence the secondary side is reconfigured (refer to the typical application schematic on page 13). The high voltage output value becomes lower than the NORMAL mode regulated value. The TL431 shunt regulator is fully OFF. In the SMPS stand by mode all the SMPS outputs are lowered except for the low voltage output that supply the wake up circuit located at the isolated side of the power supply. In that mode the secondary regulation is performed by the zener diode connected in parallel to the TL431. The secondary reconfiguration status can be detected on the SMPS primary side by measuring the voltage level present on the auxiliary winding Laux. (Refer to the Demagnetization Section). In the reconfigured status, the Laux voltage is also reduced. The V CC self powering is no longer possible thus the SMPS enters in a hiccup mode similar to the one described under the Overload condition. In the SMPS stand by mode the 3 distinct phases are: The SWITCHING PHASE: Similar to the Overload mode. The current sense clamping level is reduced according to the equation of the current sense section, page 5. The C.S. clamping level depends on the power to be delivered to the load during the SMPS stand by mode. Every switching sequence ON/OFF is terminated by an OC as long as the secondary Zener diode voltage has not been reached. When the Zener voltage is reached the ON cycle is terminated by a true PWM action. The proper SWITCHING PHASE termination must correspond to a NOC condition. The LW latch stores this NOC status. The LATCHED OFF PHASE: The MODE latch is set. The START UP PHASE is similar to the Overload Mode. The MODE latch remains in its set status (Q=1). The SWITCHING PHASE: The Stand by signal is validated and the 200 A is sourced out of the Current Sense pin Transition from Stand by to Normal The secondary reconfiguration is removed. The regulation on the low voltage secondary rail can no longer be achieved, thus at the end of the SWITCHING PHASE, no PWM condition can be encountered. The LW latch is reset. At the next WORKING PHASE a NORMAL mode status takes place. In order to become independent of the recovery time SWITCHING PHASE constant on the secondary side of the SMPS an additional reset input R2 is provided on the MODE latch. The condition I demag <24 A corresponds to the activation of the secondary reconfiguration status. The R2 reset insures a return into the NORMAL mode following the first corresponds to 1V. START UP PHASE. Pulsed Mode Duty Cycle Control During the sleep mode of the SMPS the switch S3 is closed and the control input pin 3 is connected to

15 TCL OVERSEAS HOLDINGS LIMITED Service Manual 17 a 4.6V voltage source thru a 500 resistor. The discharge rate of the V CC capacitor is given by I CC latch (device consumption during the LATCHED OFF phase) in addition to the current drawn out of the pin 3. Connecting a resistor between the Pin 3 and GND (R DPULSED ) a programmable current is drawn from the V CC through pin 3. The duration of the LATCHED OFF phase is impacted by the presence of the resistor R DPULSED. The equation 3 shows the relation to the pin 3 current. Pulsed Mode Phases Equations 1 through 8 define and predict the effective behavior during the PULSED MODE operation. The equations 6, 7, and 8 contain K, Y, and D factors. These factors are combinations of measured parameters. They appear in the parameter section K factors for pulsed mode operation page 4. In equations 3 through 8 the pin 3 current is the current defined in the above section Pulsed Mode Duty Cycle Control. 2. TDA9801-Single standard VIF-PLL demodulator and FM-PLL detector FUNCTIONAL DESCRIPTION

16 18 Service Manual TCL OVERSEAS HOLDINGS LIMITED SYMBOL PIN DESCRIPTION VIF1 1 VIF differential input 1 VIF2 2 VIF differential input 2 TOP 3 tuner AGC TakeOver Point (TOP) connection ADJ 4 phase adjust connection MUTE 5 sound mute switch connection TPLL 6 PLL time constant connection CVBS 7 CVBS (positive) video output n.c. 8 not connected AF 9 AF output DAF 10 AF amplifier decoupling capacitor connection SI 11 sound intercarrier input TAGC 12 tuner AGC output VSO 13 video and sound intercarrier output VI 14 buffer amplifier video input AFC 15 AFC output VCO1 16 VCO1 reference circuit for 2fPC VCO2 17 VCO2 reference circuit for 2fPC GND 18 ground supply (0 V) AGC 19 AGC detector capacitor connection VP 20 supply voltage (+5 V) Stage IF amplifier The VIF amplifier consists of three AC-coupled differential amplifier stages. Each differential stage comprises a feedback network controlled by emitter degeneration. AGC detector, IF AGC and tuner AGC The automatic control voltage to maintain the video output signal at a constant level is generated in accordance with the transmission standard. Since the TDA9801 is suitable for negative modulation only the peak sync pulse level is detected. The AGC detector charges and discharges capacitor CAGC to set the IF amplifier and tuner gain. The voltage on capacitor CAGC is transferred to an internal IF control signal, and is fed to the tuner AGC to generate the tuner AGC output current on pin TAGC (open-collector output). The tuner AGC takeover point level is set at pin TOP. This allows the tuner to be matched to the SAW filter in order to achieve the optimum IF input level. Frequency detector and phase detector The VIF amplifier output signal is fed into a frequency detector and into a phase detector. During acquisition the frequency detector produces a DC current proportional to the frequency difference between the input and the VCO signal. After frequency lock-in the phase detector produces a DC current proportional to the phase difference between the VCO and the input signal. The DC current of

17 TCL OVERSEAS HOLDINGS LIMITED Service Manual 19 either frequency detector or phase detector is converted into a DC voltage via the loop filter which controls the VCO frequency. Video demodulator The true synchronous video demodulator is realized by a linear multiplier which is designed for low distortion and wide bandwidth. The vision IF input signal is multiplied with the in phase component of the VCO output. The demodulator output signal is fed via an integrated low-pass filter (f g = 12 MHz) for suppression of the carrier harmonics to the video amplifier. VCO, AFC detector and travelling wave divider The VCO operates with a symmetrically connected reference LC circuit, operating at the double vision carrier frequency. Frequency control is performed by an internal variable capacitor diode. The voltage to set the VCO frequency to the actual double vision carrier frequency is also amplified and converted for the AFC output current. The VCO signal is divided-by-2 with a Travelling Wave Divider (TWD) which generates two differential output signals with a 90 degree phase difference independent of the frequency. Video amplifier The composite video amplifier is a wide bandwidth operational amplifier with internal feedback. A nominal positive video signal of 1 V (p-p) is present at pin VSO. Buffer amplifier and noise clipper The input impedance of the 7 db wideband CVBS buffer amplifier (with internal feedback) is suitable for ceramic sound trap filters. Pin CVBS provides a positive video signal of 2 V (p-p). Noise clipping is provided internally. Sound demodulation LIMITER AMPLIFIER The FM sound intercarrier signal is fed to pin SI and through a limiter amplifier before it is demodulated. The result is high sensitivity and AM suppression. The limiter amplifier consists of 7 stages which areinternally AC-coupled in order to minimizing the DC offset. FM-PLL DETECTOR The FM-PLL demodulator consists of an RC oscillator, loop filter and phase detector. The oscillator frequency is locked on the FM intercarrier signal from the limiter amplifier. As a result of this locking, the RC oscillator is frequency modulated. The modulating voltage (AF signal) is used to control the oscillator frequency. By this, the FM-PLL operates as an FM demodulator. AF AMPLIFIER The audio frequency amplifier with internal feedback is designed for high gain and high common-mode rejection. The low-level AF signal output from the FM-PLL demodulator is amplified and buffered in a low-ohmic audio output stage. An external decoupling capacitor CDAF removes the

18 20 Service Manual TCL OVERSEAS HOLDINGS LIMITED DC voltage from the audio amplifier input. By using the sound mute switch (pin MUTE) the AF amplifier is set in the mute state. 3. TDA9874A Digital TV sound demodulator/decoder SYMBOL PIN DESCRIPTION EXTIR 1 external audio input right channel EXTIL 2 external audio input left channel Vref2 3 analog reference voltage for DAC and operational amplifiers P2 4 second general purpose I/O pin OUTM 5 analog output mono VSSA4 6 analog ground supply 4 for analog back-end circuitry OUTL 7 analog output left OUTR 8 analog output right VDDA1 9 analog supply voltage 1; back-end circuitry 5 V VSSA1 10 analog ground supply 1; back-end circuitry VSSD1 11 digital ground supply 1; core circuitry VDDD1 12 digital supply voltage 1; core voltage regulator circuitry VSSD2 13 digital ground supply 2; core circuitry TP2 14 additional test pin 2; connected to VSSD for normal operation NICAM 15 serial NICAM data output (at 728 khz) TP1 16 additional test pin 1; connected to VSSD for normal operation PCLK 17 NICAM clock output (at 728 khz) ADDR1 18 first I 2 C-bus slave address modifier input XTALO 19 crystal oscillator output XTALI 20 crystal oscillator input TEST2 21 test pin 2; connected to VSSD for normal operation Iref 22 resistor for reference current generation; front-end circuitry ADDR2 23 second I 2 C-bus slave address modifier input VSSA2 24 analog ground supply 2; analog front-end circuitry VDEC 25 analog front-end circuitry supply voltage decoupling TEST1 26 test pin 1; connected to VSSD for normal operation SIF2 27 sound IF input 2 Vref1 28 reference voltage; for analog front-end circuitry SIF1 29 sound IF input 1 CRESET 30 capacitor for Power-on reset VSSA3 31 digital ground supply 3; front-end circuitry VDDA3 32 analog front-end circuitry regulator supply voltage 3 (5 V) SCL 33 I 2 C-bus serial clock input SDA 34 I 2 C-bus serial data input/output SDO 35 I 2 S-bus serial data output WS 36 I 2 S-bus word select input/output SCK 37 I2S-bus clock input/output

19 TCL OVERSEAS HOLDINGS LIMITED Service Manual 21 SYSCLK 38 system clock output VDDD3 39 digital supply voltage 3; digital I/O pads VSSD3 40 digital ground supply 3; digital I/O pads P1 41 first general purpose I/O pin MONOIN 42 analog mono input FUNCTIONAL DESCRIPTION Description of the demodulator and decoder section 1. SIF INPUTS Two inputs are provided, pin SIF1 and pin SIF2. For higher SIF signal levels the SIF input can be attenuated with an internal switchable 10 db resistor divider. As no specific filters are integrated, both inputs have the same specification giving flexibility in application. The selected signal is passed through an AGC circuit and then digitized by an 8-bit ADC operating at MHz. 2. AGC The gain of the AGC amplifier is controlled from the ADC output by means of a digital control loop employing hysteresis. The AGC has a fast attack behaviour to prevent ADC overloads, and a slow decay behaviour to prevent AGC oscillations. For AM demodulation the AGC must be switched off. When switched off, the control loop is reset and fixed gain settings can be chosen. The AGC can be controlled via the I2C-bus. 3. MIXER The digitized input signal is fed to the mixers, which mix one or both input sound carriers down to zero IF. A 24-bit control word for each carrier sets the required frequency. Access to the mixer control word registers is via the I 2 C-bus or via Easy Standard Programming (ESP). When receiving NICAM programs, a feedback signal is added to the control word of the second carrier mixer to establish a carrier-frequency loop. 4. FM AND AM DEMODULATION An FM or AM input signal is fed through a switchable band-limiting filter into a demodulator that can be used for either FM or AM demodulation. Apart from the standard (fixed) de-emphasis characteristic, an adaptive de-emphasis is available for Wegener-Panda 1 encoded satellite programs. 5. FM DECODING A 2-carrier stereo decoder recovers the left and right signal channels from the demodulated sound carriers. Both the European and Korean stereo systems are supported. Automatic FM dematrixing is also supported, which means that the FM sound mode identification

20 22 Service Manual TCL OVERSEAS HOLDINGS LIMITED (mono, stereo or dual) switches the FM dematrix directly. No loop via the microcontroller is needed. For highly overmodulated signals, a high deviation mode for monaural audio sound single carrier demodulation can be selected. NICAM decoding is still possible in high deviation mode. 6. FM IDENTIFICATION The identification of the FM sound mode is performed by AM synchronous demodulation of the pilot and narrow-band detection of the identification frequencies. The result is available via the I2C-bus interface. A selection can be made via the I2C-bus for B/G, D/K and M standards, and for three different time constants that represent different trade-offs between speed and reliability of identification. A pilot detector allows the control software to identify an analog 2-carrier (A2) transmission within approximately 0.1 s.

Model No: 21WHS3BN Version 1.0

Model No: 21WHS3BN Version 1.0 Colour TV Service Manual 2 Model: 21WHS3/BN Chassis: UOC-TDA9381 3 CONTENT SPECIFICATION... 4 THE SURVEY... 5 THE MAIN CHIPS INSTRUCTION... 6 SIGNAL PROCESS... 8 THE HORIZONTAL AND VERTICAL CIRCUIT...

More information

Baseband delay line QUICK REFERENCE DATA

Baseband delay line QUICK REFERENCE DATA FEATURES Two comb filters, using the switched-capacitor technique, for one line delay time (64 µs) Adjustment-free application No crosstalk between SECAM colour carriers (diaphoty) Handles negative or

More information

DRM compatible RF Tuner Unit DRT1

DRM compatible RF Tuner Unit DRT1 FEATURES DRM compatible RF Tuner Unit DRT1 High- Performance RF Tuner Frequency Range: 10 KHz to 30 MHz Input ICP3: +13,5dBm, typ. Noise Figure @ full gain: 14dB, typ. Receiver Factor: -0,5dB, typ. Input

More information

Product Information S N O. Portable VIP protection CCTV & Alarm System 2

Product Information S N O. Portable VIP protection CCTV & Alarm System 2 Product Information S N O Portable VIP protection CCTV & Alarm System 2 G O V E R N M E N T A L S E C U R I T Y S O L U T I VIP KIT Rapid Deployment VIP Protection Kit The VIP KIT has been designed to

More information

TDA4605 CONTROL CIRCUIT FOR SWITCH MODE POWER SUPPLIES USING MOS TRANSISTORS

TDA4605 CONTROL CIRCUIT FOR SWITCH MODE POWER SUPPLIES USING MOS TRANSISTORS CONTROL CIRCUIT FOR SWITCH MODE POWER SUPPLIES USING MOS TRANSISTORS Fold-Back Characteristic provides Overload Protection for External Diodes Burst Operation under Short-Circuit and no Load Conditions

More information

DATA SHEET. TDA8560Q 2 40 W/2 Ω stereo BTL car radio power amplifier with diagnostic facility INTEGRATED CIRCUITS. 1996 Jan 08

DATA SHEET. TDA8560Q 2 40 W/2 Ω stereo BTL car radio power amplifier with diagnostic facility INTEGRATED CIRCUITS. 1996 Jan 08 INTEGRATED CIRCUITS DATA SHEET power amplifier with diagnostic facility Supersedes data of March 1994 File under Integrated Circuits, IC01 1996 Jan 08 FEATURES Requires very few external components High

More information

Programmable Single-/Dual-/Triple- Tone Gong SAE 800

Programmable Single-/Dual-/Triple- Tone Gong SAE 800 Programmable Single-/Dual-/Triple- Tone Gong Preliminary Data SAE 800 Bipolar IC Features Supply voltage range 2.8 V to 18 V Few external components (no electrolytic capacitor) 1 tone, 2 tones, 3 tones

More information

Features. Applications. Transmitter. Receiver. General Description MINIATURE MODULE. QM MODULATION OPTIMAL RANGE 1000m

Features. Applications. Transmitter. Receiver. General Description MINIATURE MODULE. QM MODULATION OPTIMAL RANGE 1000m Features MINIATURE MODULE QM MODULATION OPTIMAL RANGE 1000m 433.05 434.79 ISM BAND 34 CHANNELS AVAILABLE SINGLE SUPPLY VOLTAGE Applications IN VEHICLE TELEMETRY SYSTEMS WIRELESS NETWORKING DOMESTIC AND

More information

AC/DC Power Supply Reference Design. Advanced SMPS Applications using the dspic DSC SMPS Family

AC/DC Power Supply Reference Design. Advanced SMPS Applications using the dspic DSC SMPS Family AC/DC Power Supply Reference Design Advanced SMPS Applications using the dspic DSC SMPS Family dspic30f SMPS Family Excellent for Digital Power Conversion Internal hi-res PWM Internal high speed ADC Internal

More information

Timing Errors and Jitter

Timing Errors and Jitter Timing Errors and Jitter Background Mike Story In a sampled (digital) system, samples have to be accurate in level and time. The digital system uses the two bits of information the signal was this big

More information

Kit 106. 50 Watt Audio Amplifier

Kit 106. 50 Watt Audio Amplifier Kit 106 50 Watt Audio Amplifier T his kit is based on an amazing IC amplifier module from ST Electronics, the TDA7294 It is intended for use as a high quality audio class AB amplifier in hi-fi applications

More information

INTEGRATED CIRCUITS DATA SHEET. TDA7000 FM radio circuit. Product specification File under Integrated Circuits, IC01

INTEGRATED CIRCUITS DATA SHEET. TDA7000 FM radio circuit. Product specification File under Integrated Circuits, IC01 INTEGRATED CIRCUITS DATA SHEET File under Integrated Circuits, IC01 May 1992 GENERAL DESCRIPTION The is a monolithic integrated circuit for mono FM portable radios, where a minimum on peripheral components

More information

FM Radio Transmitter & Receiver Modules

FM Radio Transmitter & Receiver Modules FM Radio Transmitter & Receiver Modules T5 / R5 Features MINIATURE SIL PACKAGE FULLY SHIELDED DATA RATES UP TO 128KBITS/S RANGE UPTO 300 METRES SINGLE SUPPLY VOLTAGE INDUSTRY PIN COMPATIBLE QFMT5-434 TEMP

More information

Tire pressure monitoring

Tire pressure monitoring Application Note AN601 Tire pressure monitoring 1 Purpose This document is intended to give hints on how to use the Intersema pressure sensors in a low cost tire pressure monitoring system (TPMS). 2 Introduction

More information

LM 358 Op Amp. If you have small signals and need a more useful reading we could amplify it using the op amp, this is commonly used in sensors.

LM 358 Op Amp. If you have small signals and need a more useful reading we could amplify it using the op amp, this is commonly used in sensors. LM 358 Op Amp S k i l l L e v e l : I n t e r m e d i a t e OVERVIEW The LM 358 is a duel single supply operational amplifier. As it is a single supply it eliminates the need for a duel power supply, thus

More information

TDA7318D DIGITAL CONTROLLED STEREO AUDIO PROCESSOR

TDA7318D DIGITAL CONTROLLED STEREO AUDIO PROCESSOR TDA738 DIGITAL CONTROLLED STEREO AUDIO PROCESSOR INPUT MULTIPLEXER: - 4 STEREO INPUTS - SELECTABLE INPUT GAIN FOR OPTIMAL ADAPTION TO DIFFERENT SOURCES INPUT AND OUTPUT FOR EXTERNAL EQUALIZER OR NOISE

More information

NTE2053 Integrated Circuit 8 Bit MPU Compatible A/D Converter

NTE2053 Integrated Circuit 8 Bit MPU Compatible A/D Converter NTE2053 Integrated Circuit 8 Bit MPU Compatible A/D Converter Description: The NTE2053 is a CMOS 8 bit successive approximation Analog to Digital converter in a 20 Lead DIP type package which uses a differential

More information

Series AMLDL-Z Up to 1000mA LED Driver

Series AMLDL-Z Up to 1000mA LED Driver FEATURES: Click on Series name for product info on aimtec.com Series Up to ma LED Driver Models Single output Model Input Voltage (V) Step Down DC/DC LED driver Operating Temperature range 4ºC to 85ºC

More information

www.jameco.com 1-800-831-4242

www.jameco.com 1-800-831-4242 Distributed by: www.jameco.com 1-800-831-4242 The content and copyrights of the attached material are the property of its owner. LF411 Low Offset, Low Drift JFET Input Operational Amplifier General Description

More information

100V - 100W DMOS AUDIO AMPLIFIER WITH MUTE/ST-BY THERMAL SHUTDOWN STBY-GND

100V - 100W DMOS AUDIO AMPLIFIER WITH MUTE/ST-BY THERMAL SHUTDOWN STBY-GND TDA7294 100V - 100W DMOS AUDIO AMPLIFIER WITH MUTE/ST-BY VERY HIGH OPERATING VOLTAGE RANGE (±40V) DMOS POWER STAGE HIGH OUTPUT POWER (UP TO 100W MU- SIC POWER) MUTING/STAND-BY FUNCTIONS NO SWITCH ON/OFF

More information

Harmonics and Noise in Photovoltaic (PV) Inverter and the Mitigation Strategies

Harmonics and Noise in Photovoltaic (PV) Inverter and the Mitigation Strategies Soonwook Hong, Ph. D. Michael Zuercher Martinson Harmonics and Noise in Photovoltaic (PV) Inverter and the Mitigation Strategies 1. Introduction PV inverters use semiconductor devices to transform the

More information

SD4840/4841/4842/4843/4844

SD4840/4841/4842/4843/4844 CURRENT MODE PWM CONTROLLER WITH BUILT-IN HIGH VOLTAGE MOSFET DESCRIPTION SD4840/4841/4842/4843/4844 is a current mode PWM controller with low standby power and low start current for power switch. In standby

More information

LM118/LM218/LM318 Operational Amplifiers

LM118/LM218/LM318 Operational Amplifiers LM118/LM218/LM318 Operational Amplifiers General Description The LM118 series are precision high speed operational amplifiers designed for applications requiring wide bandwidth and high slew rate. They

More information

W a d i a D i g i t a l

W a d i a D i g i t a l Wadia Decoding Computer Overview A Definition What is a Decoding Computer? The Wadia Decoding Computer is a small form factor digital-to-analog converter with digital pre-amplifier capabilities. It is

More information

Digital to Analog Converter. Raghu Tumati

Digital to Analog Converter. Raghu Tumati Digital to Analog Converter Raghu Tumati May 11, 2006 Contents 1) Introduction............................... 3 2) DAC types................................... 4 3) DAC Presented.............................

More information

AVX EMI SOLUTIONS Ron Demcko, Fellow of AVX Corporation Chris Mello, Principal Engineer, AVX Corporation Brian Ward, Business Manager, AVX Corporation

AVX EMI SOLUTIONS Ron Demcko, Fellow of AVX Corporation Chris Mello, Principal Engineer, AVX Corporation Brian Ward, Business Manager, AVX Corporation AVX EMI SOLUTIONS Ron Demcko, Fellow of AVX Corporation Chris Mello, Principal Engineer, AVX Corporation Brian Ward, Business Manager, AVX Corporation Abstract EMC compatibility is becoming a key design

More information

Supply voltage Supervisor TL77xx Series. Author: Eilhard Haseloff

Supply voltage Supervisor TL77xx Series. Author: Eilhard Haseloff Supply voltage Supervisor TL77xx Series Author: Eilhard Haseloff Literature Number: SLVAE04 March 1997 i IMPORTANT NOTICE Texas Instruments (TI) reserves the right to make changes to its products or to

More information

6.101 Final Project Report Class G Audio Amplifier

6.101 Final Project Report Class G Audio Amplifier 6.101 Final Project Report Class G Audio Amplifier Mark Spatz 4/3/2014 1 1 Introduction For my final project, I designed and built a 150 Watt audio amplifier to replace the underpowered and unreliable

More information

CTX1910_Vx.1.1 TV-Tuner Card

CTX1910_Vx.1.1 TV-Tuner Card Description: The CTX1910 is a low-cost PCI multimedia receiver and capture card for general purpose, Multimedia and Media Center Edition (MCE) PCs. To complete the MCE functionality the CTX1910 includes

More information

TV Trouble Shooting Manual

TV Trouble Shooting Manual INFORMATION SOURCE 5 TV Trouble Shooting Manual VOLUME 1 BY MASAAKI MUKAI AND RYOZO KOBAYASHI ASIAN AND PACIFIC SKILL DEVELOPMENT PROGRAMME INTERNATIONAL LABOUR OFFICE ISLAMABAD, PAKISSTAN, 1988 Appendix

More information

FEATURES DESCRIPTION APPLICATIONS BLOCK DIAGRAM. PT2248 Infrared Remote Control Transmitter

FEATURES DESCRIPTION APPLICATIONS BLOCK DIAGRAM. PT2248 Infrared Remote Control Transmitter Infrared Remote Control Transmitter DESCRIPTION PT2248 is an infrared remote control transmitter utilizing CMOS Technology. It is capable of 18 functions and a total of 75 commands. Single-shot and continuous

More information

1ED Compact A new high performance, cost efficient, high voltage gate driver IC family

1ED Compact A new high performance, cost efficient, high voltage gate driver IC family 1ED Compact A new high performance, cost efficient, high voltage gate driver IC family Heiko Rettinger, Infineon Technologies AG, Am Campeon 1-12, 85579 Neubiberg, Germany, heiko.rettinger@infineon.com

More information

ICS379. Quad PLL with VCXO Quick Turn Clock. Description. Features. Block Diagram

ICS379. Quad PLL with VCXO Quick Turn Clock. Description. Features. Block Diagram Quad PLL with VCXO Quick Turn Clock Description The ICS379 QTClock TM generates up to 9 high quality, high frequency clock outputs including a reference from a low frequency pullable crystal. It is designed

More information

PAM8403. Description. Pin Assignments. Features. Applications. Typical Applications Circuit. A Product Line of. Diodes Incorporated

PAM8403. Description. Pin Assignments. Features. Applications. Typical Applications Circuit. A Product Line of. Diodes Incorporated FILTERLESS 3W CLASS-D STEREO AUDIO AMPLIFIER Description Pin Assignments The is a 3W, class-d audio amplifier. It offers low THD+N, allowing it to achieve high-quality sound reproduction. The new filterless

More information

A CW QRP Transceiver for 20 m band. How it works I'll describe individually the three boards and the relative tuning devices.

A CW QRP Transceiver for 20 m band. How it works I'll describe individually the three boards and the relative tuning devices. A CW QRP Transceiver for 20 m band The little QRP presented in this article may be built in a gradual manner, in fact it is divided in two main modules (plus VFO), you may also complete only a single part

More information

7 OUT1 8 OUT2 9 OUT3 10 OUT4 11 OUT5 12 OUT6 13 OUT7 14 OUT8 15 OUT9 16 OUT10 17 OUT11 18 OUT12 19 OUT13 20 OUT14 21 OUT15 22 OUT16 OUT17 23 OUT18

7 OUT1 8 OUT2 9 OUT3 10 OUT4 11 OUT5 12 OUT6 13 OUT7 14 OUT8 15 OUT9 16 OUT10 17 OUT11 18 OUT12 19 OUT13 20 OUT14 21 OUT15 22 OUT16 OUT17 23 OUT18 18 CHANNELS LED DRIVER GENERAL DESCRIPTION IS31FL3218 is comprised of 18 constant current channels each with independent PWM control, designed for driving LEDs. The output current of each channel can be

More information

Diode Applications. by Kenneth A. Kuhn Sept. 1, 2008. This note illustrates some common applications of diodes.

Diode Applications. by Kenneth A. Kuhn Sept. 1, 2008. This note illustrates some common applications of diodes. by Kenneth A. Kuhn Sept. 1, 2008 This note illustrates some common applications of diodes. Power supply applications A common application for diodes is converting AC to DC. Although half-wave rectification

More information

LM138 LM338 5-Amp Adjustable Regulators

LM138 LM338 5-Amp Adjustable Regulators LM138 LM338 5-Amp Adjustable Regulators General Description The LM138 series of adjustable 3-terminal positive voltage regulators is capable of supplying in excess of 5A over a 1 2V to 32V output range

More information

Evaluating AC Current Sensor Options for Power Delivery Systems

Evaluating AC Current Sensor Options for Power Delivery Systems Evaluating AC Current Sensor Options for Power Delivery Systems State-of-the-art isolated ac current sensors based on CMOS technology can increase efficiency, performance and reliability compared to legacy

More information

VME IF PHASE MODULATOR UNIT. mod. 205-01

VME IF PHASE MODULATOR UNIT. mod. 205-01 mod. 205-01 02/06 B 1/12 INDEX 1 DESCRIPTION pg. 3 2 FRONT VIEW pg. 4-5 3 TECHNICAL CHARACTERISTICS pg. 6-7 4 OPERATING INSTRUCTIONS pg. 8 5 ANNEX LIST pg. 12 02/06 B 2/12 1 - DESCRIPTION The PHASE MODULATOR

More information

Introduction to Receivers

Introduction to Receivers Introduction to Receivers Purpose: translate RF signals to baseband Shift frequency Amplify Filter Demodulate Why is this a challenge? Interference (selectivity, images and distortion) Large dynamic range

More information

DC/DC power modules basics

DC/DC power modules basics DC/DC power modules basics Design Note 024 Ericsson Power Modules General Abstract This design note covers basic considerations for the use of on-board switch mode DC/DC power modules, also commonly known

More information

PLL frequency synthesizer

PLL frequency synthesizer ANALOG & TELECOMMUNICATION ELECTRONICS LABORATORY EXERCISE 4 Lab 4: PLL frequency synthesizer 1.1 Goal The goals of this lab exercise are: - Verify the behavior of a and of a complete PLL - Find capture

More information

TS34119 Low Power Audio Amplifier

TS34119 Low Power Audio Amplifier SOP-8 DIP-8 Pin assignment: 1. CD 8. VO2 2. FC2 7. Gnd 3. FC1 6. Vcc 4. Vin 5. VO1 General Description The TS34119 is a low power audio amplifier, it integrated circuit intended (primarily) for telephone

More information

unit : mm With heat sink (see Pd Ta characteristics)

unit : mm With heat sink (see Pd Ta characteristics) Ordering number: EN1321E Monolithic Linear IC LA4261 3.5 W 2-Channel AF Power Amplifier for Home Stereos and Music Centers Features. Minimum number of external parts required (No input capacitor, bootstrap

More information

DS1307ZN. 64 x 8 Serial Real-Time Clock

DS1307ZN. 64 x 8 Serial Real-Time Clock DS137 64 x 8 Serial Real-Time Clock www.maxim-ic.com FEATURES Real-time clock (RTC) counts seconds, minutes, hours, date of the month, month, day of the week, and year with leap-year compensation valid

More information

Spin Semiconductor FV-1 Reverb IC PN: SPN1001. Delay Memory DSP CORE. ROM and Program Control PLL. XTAL Drvr XTAL. Spin.

Spin Semiconductor FV-1 Reverb IC PN: SPN1001. Delay Memory DSP CORE. ROM and Program Control PLL. XTAL Drvr XTAL. Spin. Featuring Virtual Analog Technology PN: SPN1001 FEATURES Integrated stereo ADC and DAC 8 internal demonstration programs + 8 external programs Easy customization with external EEPROM 3 potentiometer inputs

More information

For a complete explanation of all the functions and configurations available please refer to the SC6006: Manual of operation.

For a complete explanation of all the functions and configurations available please refer to the SC6006: Manual of operation. PRELIMINARY TECHNICAL INFORMATION Three-phase Digital SCR Firing Board HIGHLIGHTS - Up to 480 V AC input supply voltage - Up to 700 V AC sync input - DSP controlled - Digital or analog input signaling

More information

Interfacing Analog to Digital Data Converters

Interfacing Analog to Digital Data Converters Converters In most of the cases, the PIO 8255 is used for interfacing the analog to digital converters with microprocessor. We have already studied 8255 interfacing with 8086 as an I/O port, in previous

More information

PS323. Precision, Single-Supply SPST Analog Switch. Features. Description. Block Diagram, Pin Configuration, and Truth Table. Applications PS323 PS323

PS323. Precision, Single-Supply SPST Analog Switch. Features. Description. Block Diagram, Pin Configuration, and Truth Table. Applications PS323 PS323 Features ÎÎLow On-Resistance (33-ohm typ.) Minimizes Distortion and Error Voltages ÎÎLow Glitching Reduces Step Errors in Sample-and-Holds. Charge Injection, 2pC typ. ÎÎSingle-Supply Operation (+2.5V to

More information

Chapter 6 PLL and Clock Generator

Chapter 6 PLL and Clock Generator Chapter 6 PLL and Clock Generator The DSP56300 core features a Phase Locked Loop (PLL) clock generator in its central processing module. The PLL allows the processor to operate at a high internal clock

More information

Technical data. General specifications. Indicators/operating means. 30 Hz Multiplex operation 30 Hz / n, n = number of sensors, n 5

Technical data. General specifications. Indicators/operating means. 30 Hz Multiplex operation 30 Hz / n, n = number of sensors, n 5 Model Number Single head system Features Parameterization interface for the application-specific adjustment of the sensor setting via the service program ULTRA 000 programmable switch outputs Hysteresis

More information

MAINTENANCE & ADJUSTMENT

MAINTENANCE & ADJUSTMENT MAINTENANCE & ADJUSTMENT Circuit Theory The concept of PLL system frequency synthesization is not of recent development, however, it has not been a long age since the digital theory has been couplet with

More information

UC3842/UC3843/UC3844/UC3845

UC3842/UC3843/UC3844/UC3845 SMPS Controller www.fairchildsemi.com Features Low Start up Current Maximum Duty Clamp UVLO With Hysteresis Operating Frequency up to 500KHz Description The UC3842/UC3843/UC3844/UC3845 are fixed frequencycurrent-mode

More information

Colour Video Monitors PVM-9045QM/9042QM/9040ME PVM-6041QM

Colour Video Monitors PVM-9045QM/9042QM/9040ME PVM-6041QM Colour Video Monitors PVM-9045QM/9042QM/9040ME Specifications GENERAL 9045QM 9042QM Colour system PAL/SECAM/NTSC/NTSC4.43 The CRT type 22 cm (9-inch) HR Trinitron Tube, pursuit 22 cm of (9-inch) excellence

More information

Fundamentals of Signature Analysis

Fundamentals of Signature Analysis Fundamentals of Signature Analysis An In-depth Overview of Power-off Testing Using Analog Signature Analysis www.huntron.com 1 www.huntron.com 2 Table of Contents SECTION 1. INTRODUCTION... 7 PURPOSE...

More information

Use and Application of Output Limiting Amplifiers (HFA1115, HFA1130, HFA1135)

Use and Application of Output Limiting Amplifiers (HFA1115, HFA1130, HFA1135) Use and Application of Output Limiting Amplifiers (HFA111, HFA110, HFA11) Application Note November 1996 AN96 Introduction Amplifiers with internal voltage clamps, also known as limiting amplifiers, have

More information

TLI4946. Datasheet TLI4946K, TLI4946-2K, TLI4946-2L. Sense and Control. May 2009

TLI4946. Datasheet TLI4946K, TLI4946-2K, TLI4946-2L. Sense and Control. May 2009 May 2009 TLI4946 High Precision Hall Effect Latches for Industrial and Consumer Applications TLI4946K, TLI4946-2K, TLI4946-2L Datasheet Rev. 1.0 Sense and Control Edition 2009-05-04 Published by Infineon

More information

LM139/LM239/LM339/LM2901/LM3302 Low Power Low Offset Voltage Quad Comparators

LM139/LM239/LM339/LM2901/LM3302 Low Power Low Offset Voltage Quad Comparators Low Power Low Offset Voltage Quad Comparators General Description The LM139 series consists of four independent precision voltage comparators with an offset voltage specification as low as 2 mv max for

More information

Isolated AC Sine Wave Input 3B42 / 3B43 / 3B44 FEATURES APPLICATIONS PRODUCT OVERVIEW FUNCTIONAL BLOCK DIAGRAM

Isolated AC Sine Wave Input 3B42 / 3B43 / 3B44 FEATURES APPLICATIONS PRODUCT OVERVIEW FUNCTIONAL BLOCK DIAGRAM Isolated AC Sine Wave Input 3B42 / 3B43 / 3B44 FEATURES AC averaging technique used to rectify, amplify, and filter 50 Hz to 400 Hz sine-wave signals. Accepts inputs of between 20 mv to 550 V rms to give

More information

DS1621 Digital Thermometer and Thermostat

DS1621 Digital Thermometer and Thermostat Digital Thermometer and Thermostat www.dalsemi.com FEATURES Temperature measurements require no external components Measures temperatures from 55 C to +125 C in 0.5 C increments. Fahrenheit equivalent

More information

TDA2040. 20W Hi-Fi AUDIO POWER AMPLIFIER

TDA2040. 20W Hi-Fi AUDIO POWER AMPLIFIER 20W Hi-Fi AUDIO POWER AMPLIFIER DESCRIPTION The TDA2040 is a monolithic integrated circuit in Pentawatt package, intended for use as an audio class AB amplifier. Typically it provides 22W output power

More information

Buffer Op Amp to ADC Circuit Collection

Buffer Op Amp to ADC Circuit Collection Application Report SLOA098 March 2002 Buffer Op Amp to ADC Circuit Collection Bruce Carter High Performance Linear Products ABSTRACT This document describes various techniques that interface buffer op

More information

On Cables and Connections A discussion by Dr. J. Kramer

On Cables and Connections A discussion by Dr. J. Kramer KRAMER ELECTRONICS LTD. On Cables and Connections A discussion by Dr. J. Kramer We are frequently asked - "what length of cable can I use for a specific application?" Seemingly a simple question, but the

More information

HT9170 DTMF Receiver. Features. General Description. Selection Table

HT9170 DTMF Receiver. Features. General Description. Selection Table DTMF Receiver Features Operating voltage: 2.5V~5.5V Minimal external components No external filter is required Low standby current (on power down mode) General Description The HT9170 series are Dual Tone

More information

LOW POWER FM TRANSMITTER SYSTEM

LOW POWER FM TRANSMITTER SYSTEM Order this document by MC28/D MC28 is a onechip FM transmitter subsystem designed for cordless telephone and FM communication equipment. It includes a microphone amplifier, voltage controlled oscillator

More information

LM1084 5A Low Dropout Positive Regulators

LM1084 5A Low Dropout Positive Regulators 5A Low Dropout Positive Regulators General Description The LM1084 is a series of low dropout voltage positive regulators with a maximum dropout of 1.5 at 5A of load current. It has the same pin-out as

More information

TDA7448 6 CHANNEL VOLUME CONTROLLER 1 FEATURES 2 DESCRIPTION. Figure 1. Package

TDA7448 6 CHANNEL VOLUME CONTROLLER 1 FEATURES 2 DESCRIPTION. Figure 1. Package 6 CHANNEL CONTROLLER FEATURES 6 CHANNEL INPUTS 6 CHANNEL OUTPUTS ATTENUATION RANGE OF 0 TO -79dB CONTROL IN.0dB STEPS 6 CHANNEL INDEPENDENT CONTROL ALL FUNCTION ARE PROGRAMMABLE VIA SERIAL BUS DESCRIPTION

More information

Note monitors controlled by analog signals CRT monitors are controlled by analog voltage. i. e. the level of analog signal delivered through the

Note monitors controlled by analog signals CRT monitors are controlled by analog voltage. i. e. the level of analog signal delivered through the DVI Interface The outline: The reasons for digital interface of a monitor the transfer from VGA to DVI. DVI v. analog interface. The principles of LCD control through DVI interface. The link between DVI

More information

Application Note SAW-Components

Application Note SAW-Components Application Note SAW-Components Principles of SAWR-stabilized oscillators and transmitters. App: Note #1 This application note describes the physical principle of SAW-stabilized oscillator. Oscillator

More information

Understanding Power Impedance Supply for Optimum Decoupling

Understanding Power Impedance Supply for Optimum Decoupling Introduction Noise in power supplies is not only caused by the power supply itself, but also the load s interaction with the power supply (i.e. dynamic loads, switching, etc.). To lower load induced noise,

More information

A Low Frequency Adapter for your Vector Network Analyzer (VNA)

A Low Frequency Adapter for your Vector Network Analyzer (VNA) Jacques Audet, VE2AZX 7525 Madrid St, Brossard, QC, Canada J4Y G3: jacaudet@videotron.ca A Low Frequency Adapter for your Vector Network Analyzer (VNA) This compact and versatile unit extends low frequency

More information

Allows the user to protect against inadvertent write operations. Device select and address bytes are Acknowledged Data Bytes are not Acknowledged

Allows the user to protect against inadvertent write operations. Device select and address bytes are Acknowledged Data Bytes are not Acknowledged Write Protect CAT24WCxxx I 2 C Serial EEPROMs. Allows the user to protect against inadvertent write operations. WP = V CC : Write Protected Device select and address bytes are Acknowledged Data Bytes are

More information

ICS650-44 SPREAD SPECTRUM CLOCK SYNTHESIZER. Description. Features. Block Diagram DATASHEET

ICS650-44 SPREAD SPECTRUM CLOCK SYNTHESIZER. Description. Features. Block Diagram DATASHEET DATASHEET ICS650-44 Description The ICS650-44 is a spread spectrum clock synthesizer intended for video projector and digital TV applications. It generates three copies of an EMI optimized 50 MHz clock

More information

TL082 Wide Bandwidth Dual JFET Input Operational Amplifier

TL082 Wide Bandwidth Dual JFET Input Operational Amplifier TL082 Wide Bandwidth Dual JFET Input Operational Amplifier General Description These devices are low cost high speed dual JFET input operational amplifiers with an internally trimmed input offset voltage

More information

MPC 4. Machinery Protection Card Type MPC 4 FEATURES. Continuous on-line Machinery Protection Card

MPC 4. Machinery Protection Card Type MPC 4 FEATURES. Continuous on-line Machinery Protection Card Machinery Protection Card Type FEATURES Continuous on-line Machinery Protection Card Real-time measurement and monitoring using state-of-the-art DSP techniques Fully VME-compatible slave interface Fully

More information

PI5A100. Precision, Wide-Bandwidth Quad SPDT Analog Switch. Description. Features. Block Diagram, Pin Configuration. Applications.

PI5A100. Precision, Wide-Bandwidth Quad SPDT Analog Switch. Description. Features. Block Diagram, Pin Configuration. Applications. Precision, Wide-Bandwidth Quad SPDT Analog Switch Features Single Supply Operation (+2V to +6V) Rail-to-Rail Analog Signal Dynamic Range Low On-Resistance (6Ω typ with 5V supply) Minimizes Distortion and

More information

The front end of the receiver performs the frequency translation, channel selection and amplification of the signal.

The front end of the receiver performs the frequency translation, channel selection and amplification of the signal. Many receivers must be capable of handling a very wide range of signal powers at the input while still producing the correct output. This must be done in the presence of noise and interference which occasionally

More information

High Speed, Low Power Monolithic Op Amp AD847

High Speed, Low Power Monolithic Op Amp AD847 a FEATURES Superior Performance High Unity Gain BW: MHz Low Supply Current:.3 ma High Slew Rate: 3 V/ s Excellent Video Specifications.% Differential Gain (NTSC and PAL).9 Differential Phase (NTSC and

More information

UNISONIC TECHNOLOGIES CO., LTD

UNISONIC TECHNOLOGIES CO., LTD UPS61 UNISONIC TECHNOLOGIES CO., LTD HIGH PERFORMANCE CURRENT MODE POWER SWITCH DESCRIPTION The UTC UPS61 is designed to provide several special enhancements to satisfy the needs, for example, Power-Saving

More information

LM5001 High Voltage Switch Mode Regulator

LM5001 High Voltage Switch Mode Regulator High Voltage Switch Mode Regulator General Description The LM5001 high voltage switch mode regulator features all of the functions necessary to implement efficient high voltage Boost, Flyback, SEPIC and

More information

Kit 27. 1W TDA7052 POWER AMPLIFIER

Kit 27. 1W TDA7052 POWER AMPLIFIER Kit 27. 1W TDA7052 POWER AMPLIFIER This is a 1 watt mono amplifier Kit module using the TDA7052 from Philips. (Note, no suffix.) It is designed to be used as a building block in other projects where a

More information

SG2525A SG3525A REGULATING PULSE WIDTH MODULATORS

SG2525A SG3525A REGULATING PULSE WIDTH MODULATORS SG2525A SG3525A REGULATING PULSE WIDTH MODULATORS 8 TO 35 V OPERATION 5.1 V REFERENCE TRIMMED TO ± 1 % 100 Hz TO 500 KHz OSCILLATOR RANGE SEPARATE OSCILLATOR SYNC TERMINAL ADJUSTABLE DEADTIME CONTROL INTERNAL

More information

TRIPLE PLL FIELD PROG. SPREAD SPECTRUM CLOCK SYNTHESIZER. Features

TRIPLE PLL FIELD PROG. SPREAD SPECTRUM CLOCK SYNTHESIZER. Features DATASHEET ICS280 Description The ICS280 field programmable spread spectrum clock synthesizer generates up to four high-quality, high-frequency clock outputs including multiple reference clocks from a low-frequency

More information

Supertex inc. HV256. 32-Channel High Voltage Amplifier Array HV256. Features. General Description. Applications. Typical Application Circuit

Supertex inc. HV256. 32-Channel High Voltage Amplifier Array HV256. Features. General Description. Applications. Typical Application Circuit 32-Channel High Voltage Amplifier Array Features 32 independent high voltage amplifiers 3V operating voltage 295V output voltage 2.2V/µs typical output slew rate Adjustable output current source limit

More information

FM TRANSMITTER & RECEIVER HYBRID MODULES. FM-RTFQ SERIES FM-RRFQ SERIES. Transmitter. Receiver. Applications

FM TRANSMITTER & RECEIVER HYBRID MODULES. FM-RTFQ SERIES FM-RRFQ SERIES. Transmitter. Receiver. Applications FM Radio Transmitter & Receivers Available as or or 868MHz Transmit Range up to 20m Miniature Packages Data Rate up to 9.6Kbps No Adjustable Components Very Stable Operating Frequency Operates from 20

More information

Cumbria Designs T-1. SSB/CW Filter kit (4.9152MHz) User Manual

Cumbria Designs T-1. SSB/CW Filter kit (4.9152MHz) User Manual Cumbria Designs T-1 SSB/CW Filter kit (4.9152MHz) User Manual CONTENTS 1 INTRODUCTION 2 2 CIRCUIT DESCRIPTION 2 3 ASSEMBLY 2 4 TESTING 4 The Steading Stainton PENRITH Cumbria CA11 0ES UK 1 Introduction

More information

DDX 7000 & 8003. Digital Partial Discharge Detectors FEATURES APPLICATIONS

DDX 7000 & 8003. Digital Partial Discharge Detectors FEATURES APPLICATIONS DDX 7000 & 8003 Digital Partial Discharge Detectors The HAEFELY HIPOTRONICS DDX Digital Partial Discharge Detector offers the high accuracy and flexibility of digital technology, plus the real-time display

More information

NCP1612. Enhanced, High-Efficiency Power Factor Controller

NCP1612. Enhanced, High-Efficiency Power Factor Controller Enhanced, High-Efficiency Power Factor Controller The NCP1612 is designed to drive PFC boost stages based on an innovative Current Controlled Frequency Fold back (CCFF) method. In this mode, the circuit

More information

Rail-to-Rail, High Output Current Amplifier AD8397

Rail-to-Rail, High Output Current Amplifier AD8397 Rail-to-Rail, High Output Current Amplifier AD8397 FEATURES Dual operational amplifier Voltage feedback Wide supply range from 3 V to 24 V Rail-to-rail output Output swing to within.5 V of supply rails

More information

Design of a TL431-Based Controller for a Flyback Converter

Design of a TL431-Based Controller for a Flyback Converter Design of a TL431-Based Controller for a Flyback Converter Dr. John Schönberger Plexim GmbH Technoparkstrasse 1 8005 Zürich 1 Introduction The TL431 is a reference voltage source that is commonly used

More information

LM1036 Dual DC Operated Tone/Volume/Balance Circuit

LM1036 Dual DC Operated Tone/Volume/Balance Circuit LM1036 Dual DC Operated Tone/Volume/Balance Circuit General Description The LM1036 is a DC controlled tone (bass/treble), volume and balance circuit for stereo applications in car radio, TV and audio systems.

More information

Modification Details.

Modification Details. Front end receiver modification for DRM: AKD Target Communications receiver. Model HF3. Summary. The receiver was modified and capable of receiving DRM, but performance was limited by the phase noise from

More information

M68EVB908QL4 Development Board for Motorola MC68HC908QL4

M68EVB908QL4 Development Board for Motorola MC68HC908QL4 M68EVB908QL4 Development Board for Motorola MC68HC908QL4! Axiom Manufacturing 2813 Industrial Lane Garland, TX 75041 Email: Sales@axman.com Web: http://www.axman.com! CONTENTS CAUTIONARY NOTES...3 TERMINOLOGY...3

More information

LDS8720. 184 WLED Matrix Driver with Boost Converter FEATURES APPLICATION DESCRIPTION TYPICAL APPLICATION CIRCUIT

LDS8720. 184 WLED Matrix Driver with Boost Converter FEATURES APPLICATION DESCRIPTION TYPICAL APPLICATION CIRCUIT 184 WLED Matrix Driver with Boost Converter FEATURES High efficiency boost converter with the input voltage range from 2.7 to 5.5 V No external Schottky Required (Internal synchronous rectifier) 250 mv

More information

Current Loop Tuning Procedure. Servo Drive Current Loop Tuning Procedure (intended for Analog input PWM output servo drives) General Procedure AN-015

Current Loop Tuning Procedure. Servo Drive Current Loop Tuning Procedure (intended for Analog input PWM output servo drives) General Procedure AN-015 Servo Drive Current Loop Tuning Procedure (intended for Analog input PWM output servo drives) The standard tuning values used in ADVANCED Motion Controls drives are conservative and work well in over 90%

More information

THE R551N RECEIVER FAQ FAULT FINDING THE REDIFON COMMUNICATIONS RECEIVER R551N. Date: October 10th 1995 by: Jan Verduyn G5BBL

THE R551N RECEIVER FAQ FAULT FINDING THE REDIFON COMMUNICATIONS RECEIVER R551N. Date: October 10th 1995 by: Jan Verduyn G5BBL THE R551N RECEIVER FAQ FAULT FINDING THE REDIFON COMMUNICATIONS RECEIVER R551N Introduction: Date: October 10th 1995 by: Jan Verduyn G5BBL Recently a number of Redifon R551N receivers have appeared on

More information

PIEZO FILTERS INTRODUCTION

PIEZO FILTERS INTRODUCTION For more than two decades, ceramic filter technology has been instrumental in the proliferation of solid state electronics. A view of the future reveals that even greater expectations will be placed on

More information

RGB for ZX Spectrum 128, +2, +2A, +3

RGB for ZX Spectrum 128, +2, +2A, +3 RGB for ZX Spectrum 128, +2, +2A, +3 Introduction... 2 Video Circuitry... 3 Audio Circuitry... 8 Lead Wiring... 9 Testing The Lead... 11 Spectrum +2A/+3 RGB Differences... 12 Circuitry Calculations...

More information

DS2187 Receive Line Interface

DS2187 Receive Line Interface Receive Line Interface www.dalsemi.com FEATURES Line interface for T1 (1.544 MHz) and CEPT (2.048 MHz) primary rate networks Extracts clock and data from twisted pair or coax Meets requirements of PUB

More information